The present invention relates to an editing control apparatus used for editing audio-visual (AV) information.
Generally, editing of AV information using a conventional editing control apparatus is performed by connecting a playback VCR (video cassette recorder) and a record VCR to the editing control apparatus. In such editing, a playback tape on which various pieces of AV information are recorded is set in the playback VCR, while a record tape for recording edited AV information is loaded into the record VCR. Editing of AV information is done by recording only necessary materials, which are selected from the various pieces of AV information obtained, onto the record tape in the desired order by using the record VCR. In this editing work, playback start positions (P-IN points) and playback end positions (P-OUT points) on the playback tape on which the various pieces of AV information are recorded, and record start positions (R-IN points), etc. on the record tape, are each treated as one unit of edit information (one event information unit), and these event information units are recorded in the desired order on the record tape.
The word "event" here represents one unit of image information in AV information, and refers, for example, to image information of one scene. In the above example, one event refers to AV information recorded between the playback start position (P-IN point) and playback end position (P-OUT point) on the playback tape.
In this way, a plurality of event information are recorded on the record tape in order of play back, and an edit decision list (hereinafter abbreviated EDL) is created. Besides the playback start positions (P-IN points) and playback end positions (P-OUT points) on the playback tape and the record start positions (R-IN points) on the record tape, transition mode information indicating a change from the immediately previous event to the current event (for example, information indicating a cut at which the entire screen changes from one scene to another instantaneously, or a special transition effect such as a wipe or a fade) is also treated as one event information unit. In the EDL, a plurality of such event information units are recorded in order of play back.
In the editing of AV information for news programs, such editing work must be done within a short limited time so as to ensure the presentation of appropriate AV information material for display on the screen in correct timing with the narration being read by an announcer. In such editing work, the editor assembles event information while viewing AV information material. Previously, it has been standard practice to first assemble the event information in the editor's mind and then start editing work using a conventional editing control apparatus. After completing the editing work, however, there has often been the case that the editor has to work on corrections to the completed EDL until the deadline to see if the edit can be further improved.
When editing AV information in this way by recording on the record tape using the conventional editing control apparatus, the editing work required at least recording time for recording on the record tape. Further, when executing a revision works using a tape as a recording medium, if a time duration of a revision portion on the tape (the tape length of the revision portion) is different from the time duration on the tape before the revision, editing work of the recorded information on the tape after the revision portion has had to be redone over again. Such editing work has had the problem that revising the AV information materials on the tape takes a long time.